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Stock-Based Compensation (Tables) | 3 Months Ended
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Mar. 31, 2024
Share-Based Payment Arrangement [Abstract] |
Share-Based Payment Arrangement, Option, Activity | The following table summarizes stock option activity during the three months ended March 31, 2024:
| Stock Options |  | Weighted- Average Exercise Price
Options outstanding at December 31, 2023 | 371,313 |  | $ | 59.92 |
Granted | 95,470 |  | 33.52 |
Exercised | - |  | -
Forfeited | (12,912) |  | 73.73 |
Expired | (1,632) |  | 78.59 |
Options outstanding at March 31, 2024 | 452,239 |  | $ | 53.89 |
Exercisable at March 31, 2024 | 183,461 |  | $ | 73.15 |
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions | The following table provides the assumptions used in the Black-Scholes pricing model valuation of options during the three months ended March 31, 2024 and 2023:
| Three Months Ended March 31,
| 2024 |  | 2023
Risk-free interest rate | 4.28% |  | 3.90% - 4.55%
Expected life (years) | 6.25 |  | 2.00 - 6.25
Expected volatility | 50.62% |  | 49.23% - 55.92%
Expected dividend yield | 0% |  | 0%
Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity | The following table summarizes restricted stock activity during the three months ended March 31, 2024:
| Restricted Stock |  | Weighted- Average Grant Date Fair Value Per Share
Restricted stock at December 31, 2023 | 653,465 |  | $ | 45.89 |
Granted | 76,078 |  | 33.52 |
Restrictions lapsed | (45,886) |  | 76.14 |
Forfeited | (13,390) |  | 47.78 |
Restricted stock at March 31, 2024 | 670,267 |  | $ | 42.37 |
Schedule of Nonvested Performance-Based Units Activity | The following table summarizes performance stock activity during the three months ended March 31, 2024:
| Performance Stock |  | Weighted- Average Grant Date Fair Value Per Share
Performance stock at December 31, 2023 | 107,097 |  | $ | 74.08 |
Granted | 79,436 |  | 48.20 |
Restrictions lapsed | - |  | - |
Performance change | (2,772) |  | 227.14 |
Forfeited | - |  |
Performance stock at March 31, 2024 | 183,761 |  | $ | 60.58 |
Schedule of Share-based Payment Award, Awards Other Than Stock Options, Valuation Assumptions | The following table provides the assumptions used in the Monte Carlo pricing model valuation of PSUs during the three months ended March 31, 2024 and 2023:
| Three Months Ended March 31,
| 2024 |  | 2023
Risk-free interest rate | 4.37% |  | 4.35%
Expected life (years) | 2.88 |  | 2.88
Expected volatility | 51.40% |  | 58.00%
Expected dividend yield | 0% |  | 0%
Schedule of Share-Based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions | The following table presents the assumptions used to estimate the fair value of the ESPP during the three months ended March 31, 2024 and 2023:
| Three Months Ended March 31,
| 2024 |  | 2023
Risk-free interest rate | 5.16% |  | 4.60%
Expected life (months) | 6.00 |  | 6.00
Expected volatility | 47.92% |  | 67.84%
Expected dividend yield | 0% |  | 0%

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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of employee stock purchase plans, including, but not limited to: (a) expected term, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 718 -SubTopic 10 -Subparagraph (f)(2) -Name Accounting Standards Codification -Paragraph 2 -Section 50 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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